1. Field of the Invention
The present invention relates to a throttle valve control apparatus for controlling a flow amount of intake air of an internal combustion engine and a motor vehicle.
2. Description of the Prior Art
An electrical control type throttle apparatus opening and closing a throttle valve of an internal combustion engine by a motor-driven actuator (for example, a direct current motor, a stepping motor, a torque motor and a brushless motor) is put into practice.
The electrical control type throttle apparatus is structured such as to control an optimum throttle valve angle (throttle valve opening degree) corresponding to an engine state on the basis of an opening degree signal of an accelerator pedal and a traction control signal. For this purpose, a sensor for detecting an angle of the throttle valve, so-called a throttle sensor (which may be sometimes called as an opening degree meter or a throttle position sensor) is attached to a throttle body.
A potentiometer system is generally employed in the throttle sensor, and a brush (a sliding element) rotating together with a throttle valve shaft slides on a resisting body, thereby outputting a potential difference signal (a sensor detecting signal) corresponding to a throttle valve opening degree (for example, refer to Japanese Unexamined Patent Publication No. 9-32588).
This kind of conventionally used throttle sensor is structured such that the brush is in contact with a variable resistance and a conductor formed on a resistance base plate so as to slide thereon. Accordingly, a service life of the sensor is short and the sensor is frequently in trouble. A double route of sensor is employed so as to detect a trouble of sensor and mutually back up, however, this can not basically solve the problem.
Further, since the trouble mentioned above is generated in the conventional motor vehicle at a high possibility, and a control parameter is controlled by an output of the sensor having a short service life, an accuracy for operating and controlling the internal combustion engine is low.
There has been known Japanese Patent No. 2845884 as a structure for detecting the opening degree of the throttle valve in a non-contact manner.
An object of the present invention is to provide a throttle valve control apparatus provided with a throttle sensor which is in trouble at a low possibility and has a long service life.
In particular, there is suggested some structures for compactly attaching a non-contact type sensor to a throttle control apparatus so as to constitute a part of the apparatus.
Further, there is suggested structures for removing a magnetic noise and a bad influence against a magnetic characteristic.
Further, another object is to improve a throttle sensor corresponding to one of elements for controlling control parameters of an internal combustion engine so as to improve an operation control accuracy of the internal combustion engine.
In order to achieve the objects mentioned above, the present invention proposes the following throttle valve control apparatuses and motor vehicles.
In accordance with a first aspect of the present invention, there is provided a throttle valve control apparatus of an internal combustion engine comprising:
a throttle valve shaft or, as hereinafter also referred to, valve throttle axis rotated by a motor-driven actuator;
an alternate magnet mounted to the throttle valve axis;
a cover to which an element for detecting a change of magnetic flux of the alternate magnet is mounted;
the cover being mounted to a throttle body to which the motor-driven actuator is mounted; and
an output of the element constituting a function of an opening degree of the throttle valve.
In accordance with a second aspect of the present invention, there is provided a throttle valve control apparatus of an internal combustion engine comprising:
a throttle body provided with a throttle valve controlling an amount of intake air;
a throttle sensor detecting a rotational angle of an axis to which the throttle valve is mounted; and
a motor-driven actuator in which a command value is adjusted in accordance with an electric signal output from the throttle sensor,
wherein the throttle sensor comprises:
an element mounted to one end of the throttle valve axis; and
another element attached to a cover member fixed to the throttle body so as to cover the axial end portion, and
wherein a magnetic physical amount between the pair of elements is varied in accordance with a change of the rotational angle of the throttle axis, and the element mounted to the cover member outputs an electric signal relating to the rotational angle of the axis in response to the change of the magnetic physical amount.
In accordance with a third aspect of the present invention, there is provided a motor vehicle comprising:
an element outputting an electric signal relating to an opening degree of a throttle valve on the basis of a magnetic signal of a magnet mounted to an axial end of the throttle valve,
wherein a control parameter of an engine is adjusted in accordance with a change of the electric signal output from the element.
In accordance with a fourth aspect of the present invention, there is provided a throttle control apparatus of an internal combustion engine structured such as to transmit a rotation of a motor to a throttle valve axis via a gear fixed to the throttle valve axis,
wherein a rotational angle of the throttle valve axis is detected by a magnetic type throttle sensor comprising a magnet and a Hall element, and the gear is formed by a resin material.
In accordance with a fifth aspect of the present invention, there is provided a throttle valve control apparatus of an internal combustion engine structured such that a rotary axis of a motor and a throttle valve axis are arranged in parallel and a rotation of the rotary axis of the motor is transmitted to the throttle valve axis via a reduction gear,
wherein a magnetic type throttle sensor comprising a magnet and a Hall element is mounted so as to be capable of detecting a rotational angle of the throttle valve axis, and
wherein a rotary axis of a gear positioned in a middle of a torque transmission path between the rotary axis of the motor and the throttle valve axis is formed by a magnetic material.
In accordance with a sixth aspect of the present invention, there is provided a throttle valve control apparatus of an internal combustion engine structured such as to detect a rotational angle of a throttle valve driven by a motor,
wherein a magnet is mounted to the throttle valve axis;
wherein Hall elements are arranged at positions facing to each other with respect to the magnet and a stator corresponding to a magnetic path is attached between the Hall elements, and
wherein the motor is mounted to a position a uniform distance apart from the both Hall elements.
In accordance with a seventh aspect of the present invention, there is provided a throttle valve control apparatus of an internal combustion engine structured such that a sensor for detecting a rotational angle of a throttle valve driven by a motor is provided and a rotary axis of the motor and the throttle valve axis are arranged in parallel,
wherein a magnet is mounted to the throttle valve axis,
wherein Hall elements are arranged at positions facing to each other with respect to the magnet and a stator corresponding to a magnetic path is attached between the Hall elements, and
wherein the both Hall elements are arranged out of a circular arc having a radius corresponding to a distance between the rotary axis of the motor and a center of the throttle valve axis.
In accordance with an eighth aspect of the present invention, there is provided a throttle valve control apparatus of an internal combustion engine comprising:
a magnet mounted to a throttle valve axis to which a throttle valve is mounted; and
a cover fixed to a throttle body so as to cover the magnet portion,
wherein a Hall element sensitive to a change of a magnetic physical amount of the magnet and a signal processing circuit converting an output of the Hall element into a predetermined electric signal are mounted to the cover.
In accordance with a ninth aspect of the present invention, there is provided a throttle valve control apparatus of an internal combustion engine structured such that a rotary axis of a motor and a throttle valve axis are arranged in parallel and a rotation of the rotary axis of the motor is transmitted to the throttle valve axis via a reduction gear,
wherein a cover is mounted to a throttle body so as to cover the reduction gear, and
wherein a magnetic type throttle sensor comprising a magnet and a Hall element is mounted between an end surface of a gear fixed to the throttle valve axis and the cover so as to be capable of detecting a rotational angle of the throttle valve axis.
In accordance with a tenth aspect of the present invention, there is provided a throttle valve control apparatus of an internal combustion engine comprising:
a magnet mounted to an end portion of a throttle valve axis rotated by a motor;
an element detecting a rotational angle of the throttle valve axis in cooperation with the magnet; and
a spring holding the magnet at a predetermined opening position of opening degree when energizing of the motor is shut out, the spring being attached to a periphery of the throttle valve axis.
In accordance with an eleventh aspect of the present invention, there is provided a throttle valve control apparatus comprising:
a magnet mounted to a throttle valve axis rotated by a motor;
an element detecting a rotational angle of the throttle valve axis in cooperation with the magnet; and
the element being constituted by two components arranged under a magnetic influence of the magnet so as to be backed up by each other.